Treadmill with curved axles supporting the belt

ABSTRACT

A treadmill utilizing an endless belt which permits a user to run while remaining in one place. Curved axles supporting driving wheels are employed to minimize the number of driving wheels and axles employed. Each axle rotatably supports one wheel at its center and one wheel at each end. These axles are curved in a horizontal plane so that the center wheel is offset from the end wheels.

United States Patent Evan H. Berlin l 19 Dunn Ave., Lake City, Pa. 16423 Appl. No. 38,666

Filed May 19, 1970 Patented Sept. 28, 1971 Inventor TREADMILL WITH CURVED AXLES SUPPORTING THE BELT 4 Claims, 6 Drawing Figs.

ILLS. Cl 272/69 A63!) 23/06 272/69;

[56] References Cited UNITED STATES PATENTS 1,064,968 6/1913 Hagen 272/69 i Primary Examiner-Richard C. Pinkham Assistant Examiner-Richard Dror ABSTRACT: A treadmill utilizing an endless belt which permits a user to run while remaining in one place. Curved axles supporting driving wheels are employed to minimize the number of driving wheels and axles employed. Each axle rotutably supports one wheel at its center and one wheel at each end. These axles are curved in a horizontal plane so that the center wheel is offset from the end wheels.

TREADMILL WITH CURVED AXLES SUPPORTING THE BELT SUMMARY OF THE INVENTION A rectangular frame supports a plurality of transversely extending horizontal axles. These axles have at each end and at the midpoint a separate driving wheel freely rotatable thereabout. Some of the axles as viewed in a horizontal plane are curved intermediate their ends to offset the center wheel from the end wheels. An endless belt freely rotatable in the frame is wrapped around the axles to engage the wheels and to be spaced from the axles. A user runs on top of the belt which rotates with the wheels to enable the user to remain in one place while running. Use of the offset wheels enables greater separation between adjacent axles for a given size of frame over that obtainable when straight parallel axles are used whereby the number of axles and driving wheels is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a top cutaway view of my invention; FIG. 2 is a cross-sectional end view thereof; FIG. 3 is a detail top view thereof;

FIG. 4 is a detail end view thereof;

FIG. 5 is a cross sectional side view thereof; and FIG. 6 is a perspective view thereof.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to FIGS. 1-6, a hollow rectangular frame 10 having open top and bottom surfaces is provided at one end with manually adjustable screws 12 to vary the separation between this end and the ground, floor or other supporting surface whereby the frame can be inclined or level. As the angle of inclination is increased, the energy required to operate the apparatus is increased whereby more strenuous exercise is involved. A handle 14 to be used, when desired, as a support by a user is secured to, and extends upward from this one end.

A plurality of spaced horizontal axles having freely rotatable driving wheels 16 at each end extend within the frame between opposite sides. The axles 18 immediately adjacent each end are straight and parallel; all other axles 22 curve in the same direction, as viewed in the horizontal plane, between their ends whereby the midpoint of each axle is equidistantly offset from both ends. (These axles, as viewed in vertical planes, do not curve). An additional driving wheel 24 is secured to the midpoint of each axle and is freely rotatable thereabout. All wheels 16 and 24 are parallel and are coplanar. However, each wheel 24 is offset from the corresponding wheels 16.

An endless belt 26 having top and bottom horizontal surfaces is disposed in the frame and is wrapped about the axles and wheels in such manner as to engage the periphery of the wheels and to be spaced from the axles. The longitudinal direction of rotation of the belt extends transversely to the axles, A user can then run on the structure while remaining in one place in the usual manner utilizing a treadmill.

Were all axles to be straight and parallel, a certain quantity of axles and wheels would be required with a given geometry to provide proper performance regardless of the position of the users feet on the belt. By using curved axles and offset wheels, fewer axles and wheels are required for the same geometry. Note that straight axles 1.8 are used to provide proper clearances adjacent the ends of the frame.

While I have described my invention with particular reference to the drawings such is not to be considered as limiting its actual scope.

Having thus described this invention what is asserted as new 1. Exercise apparatus comprising: a hollow rectangular frame having open top and bottom surfaces; a plurality of horizontal spaced axles extending in spaced horizontally coplanar positions between opposite sides of the frame, at least some of these axles being curved in a horizontal plane whereby the midpoint of each curved axle is in the same horizontal plane, as but is disposed offset and equidistantly spaced from both ends thereof;

a like plurality of pairs of driving wheels, each wheel in the pair being rotatably disposed about a corresponding end of a corresponding axle, all of said wheel pairs being parallel and coplanar;

an additional and like plurality of individual driving wheels parallel to and coplanar with said wheel pairs, each individual wheel being rotatable about the midpoint of the corresponding axle; and

an endless belt having a longitudinal direction of rotation extending transversely to said axles, said belt being wrapped about and in peripheral contact with all of said wheels and spaced from said axles.

2. Apparatus as set forth in claim I wherein others of said axles are straight and parallel.

3. Apparatus as set forth in claim 2. wherein there are two straight axles, each straight axle being disposed adjacent a corresponding end of the frame.

4. Apparatus as set forth in claim 3 further including manually adjustable means secured to one end of said frame to vary the angle of inclination of said frame with respect to the horizontal. 

1. Exercise apparatus comprising: a hollow rectangular frame having open top and bottom surfaces; a plurality of horizontal spaced axles extending in spaced horizontally coplanar positions between opposite sides of the frame, at least some of these axles being curved in a horizontal plane whereby the midpoint of each curved axle is in the same horizontal plane, as but is disposed offset and equidistantly spaced from both ends thereof; a like plurality of pairs of driving wheels, each wheel in the pair being rotatably disposed about a corresponding end of a corresponding axle, all of said wheel pairs being parallel and coplanar; an additional and like plurality of individual driving wheels parallel to and coplanar with said wheel pairs, each individual wheel being rotatable about the midpoint of the corresponding axle; and an endless belt having a longitudinal direction of rotation extending transversely to said axles, said belt being wrapped about and in peripheral contact with all of said wheels and spaced from said axles.
 2. Apparatus as set forth in claim 1 wherein others of said axles are straight and parallel.
 3. Apparatus as set forth in claim 2 wherein there are two straight axles, each straight axle being disposed adjacent a corresponding end of the frame.
 4. Apparatus as set forth in claim 3 further including manually adjustable means secured to one end of said frame to vary the angle of inclination of said frame with respect to the horizontal. 